The present invention relates to the production of thin film transistors in which the conductivity of source and/or drain regions should be high, e.g. for driving liquid crystal displays (LCD).
From the prior art it is known to produce source and/or drain regions for a thin film transistor with a high conductivity, e.g. greater than or equivalent to 1.OMEGA..sup.-1 cm.sup.-1 by means of ion implantation. Such ion implantation is cumbersome, requires complicated equipment and is difficult to apply to relatively large surfaces Further,. it is known from EP-A-0062079 to produce a semiconductor layer in microcrystalline form by means of a PECVD reactor.
U.S. Pat. No. 4625224 relates to a thin film transistor having 0.001-5 atomic %CL.
EP-A-0161555 relates to a polycrystalline silicon thin film transistor structure having source and drain regions in amorphous form.
Also US-A-4,485,121, EP-A-0232619 and GB-A-2156385 show structures using amorphous materials.
Further the following publications are known to the applicant: EP-0132076, EP-0200552, EP-0201270, EP-0206649, EP-0206650, EP-0228295, EP-0228870, EP-0229518, EP-0229707, EP-0232148, EP-0234094, EP-0240305, EP-0240306, EP-0240314, EP-0241311, EP-0241316, EP-0241317, EP-0242207, EP-0243074; and the article "Very-low-Temperature Silicon Epitaxy by Plasma-DVD Using SiH.sub.4 -PH.sub.3 -H.sub.2 Reactants for Bipolar Devices" from the Japanese Journal of Applied Physics, Vol. 27 No. 4, April 1988, pages L493-L495.